1. Field of the Invention
This document is directed to a liquid crystal display, and more particularly to a liquid crystal display that can improve heat radiation properties as well as may comply with a slim trend of displays.
2. Discussion of the Related Art
Importance of display devices as image information transmitting media has been recently emphasized in the information-oriented society. Cathode ray tubes (CRTs) or brown tubes, which have been mainly employed for display devices, had problems in terms of weight and volume. Various types of flat panel displays are being developed to overcome the shortcoming of the CRTs.
Flat panel displays include liquid crystal displays (LCDs), field emission displays (FEDs), plasma display panels (PDPs), and electro-luminescence (ELs), most of which have been commercially available.
Among these, liquid crystal displays have an increasing applicable range because of light-weight, thin, low-power consumption features. According to this trend, liquid crystal displays have been adopted for portable computers such as laptop computers, office automation apparatuses, audio/video devices, indoor/outdoor advertisement displays, navigators, and rear view detectors. A liquid crystal display displays a desired image by adjusting the amount of transmitting light beams according to an image signal applied to multiple switches for control, which are arranged in a matrix pattern. Liquid crystal displays have been sharply grown up to have a large size and high resolution because of recent achievements of mass production technology and research and development. In addition, liquid crystal displays exhibit a huge amount of demand even in small and middle sized businesses owing to development of mobile display-related industries.
FIG. 1 is a view illustrating a rear side of a liquid crystal display according to the related art.
Referring to FIG. 1, a related art liquid crystal display includes a liquid crystal panel having two glass substrates and a liquid crystal layer arranged between the two glass substrates and having dielectric anisotropy; a backlight unit having light sources and a bottom cover 5 receiving a PCB 30 for light source that generates a light source driving signal to be supplied to the light sources, the backlight unit illuminating the liquid crystal panel; driving integrated circuits (ICs) applying a panel driving signal to signal lines provided to the liquid crystal panel; a main printed circuit board (PCB) 10 for generating a panel driving signal; a flexible printed circuit (FPC) 20 for supplying a panel driving signal from the main PCB 10 to the driving ICs; and a wire 40 for power supply supplying a power signal from the main PCB 10 to the PCB 30 for light source. The main PCB 10 is connected to a side of the FPC 20 and located on the rear surface of the bottom cover 5. A first shield cover 50 and a second shield cover 60 are arranged over the main PCB 10 and the FPC 20, respectively. The first shield cover 50 is fixed onto the main PCB 10 through a screw 70 to protect the main PCB 10 from external temperature or moisture. The second shield cover 60 surrounds the FPC 20 and is fixed onto the rear surface of the bottom cover 5 by an adhesive tape to protect the FPC 20 from external temperature or moisture. The PCB 30 for light source is located at an edge of the liquid crystal display while being surrounded by the bottom cover 5. The main PCB 10 is electrically connected to the bottom cover 5 through a conductive tape 80. The conductive tape 80 guides static electricity from the main PCB 10 to the bottom cover 5 which is grounded to protect circuit elements mounted on the main PCB 10 from the static electricity.
However, these related art liquid crystal displays have the following problems.
Firstly, the PCB for light source emits a great deal of heat because of driving the multiple light sources. The related art liquid crystal display is very weak in heat radiation of the PCB for light source since the PCB for light source is surrounded by the bottom cover and the rear surface of the bottom cover is covered by the main PCB, the first shield cover and the second shield cover which cause the generated heat to be trapped.
Secondly, the related art liquid crystal display has a limitation in reducing its thickness due to the main PCB located on the rear surface of the bottom cover, causing it difficult to allow the display to adapt for the slim trend in thickness.
Finally, the related art liquid crystal display requires many units for assembling a module, thus causing increase in producing costs and complexity of assembling processes. Particularly, the first shield cover, the screw, the second shield cover, the adhesive tape, the conductive tape, and wire for power supply may be primary factors of increasing costs and complicating assembling processes.